package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.bean.copier.CopyOptions;
import cn.hutool.core.lang.UUID;
import cn.hutool.core.util.RandomUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.LoginFormDTO;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.User;
import com.hmdp.mapper.UserMapper;
import com.hmdp.service.IUserService;
import com.hmdp.utils.RegexUtils;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.connection.BitFieldSubCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import javax.servlet.http.HttpSession;

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.TimeUnit;

import static com.hmdp.utils.RedisConstants.*;
import static com.hmdp.utils.SystemConstants.USER_NICK_NAME_PREFIX;

/**
 * <p>
 * 服务实现类
 * </p>
 */
@Service
@Slf4j
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;


    /**
     * 发送验证码
     * @param phone 手机号
     * @param session session
     * @return Result.ok()
     */
    @Override
    public Result sendCode(String phone, HttpSession session) {
        //1.校验手机号
        if (RegexUtils.isPhoneInvalid(phone)) {
            //2.手机号码不符合规范
            return Result.fail("手机号格式错误");
        }
        //3.符合，生成验证码
        String code = RandomUtil.randomNumbers(6);
        //4.保存验证码到 redis
        stringRedisTemplate.opsForValue().set(LOGIN_CODE_KEY + phone,code,LOGIN_CODE_TTL, TimeUnit.MINUTES);

        //5.发送验证码(阿里云平台)
        log.debug("发送验证码成功，验证码：{}",code);
        return Result.ok();
    }

    /**
     * 验证验证码
     * @param loginForm 登录实体类，有手机，密码，验证码
     * @param session session
     * @return Result.ok()
     */
    @Override
    public Result login(LoginFormDTO loginForm, HttpSession session) {
        log.error("执行到了login==========");
        String phone = loginForm.getPhone();
        //1.校验手机号
        if (RegexUtils.isPhoneInvalid(phone)) {
            return Result.fail("用户手机号错误");
        }

        //2.校验验证码 从redis获取
        String cacheCode = stringRedisTemplate.opsForValue().get(LOGIN_CODE_KEY + phone);
        String code = loginForm.getCode();
        //3.验证码不一致 cacheCode == null未发送验证码或验证码过期
        if(cacheCode == null || !cacheCode.equals(code)){
            return Result.fail("验证码不一致");
        }

        //4.根据手机号到数据库查询用户
        User user = query().eq("phone", phone).one();
        //5.判断是否存在
        if(user == null){
            //6.不存在，新用户 写入数据库
            log.info("用户不存在，创建新用户============");
            user = createUserWithPhone(phone);
        }

        //7.保存用户信息到 redis
        //7.1随机生成token，作为登录令牌
        String token = UUID.randomUUID().toString(true);
        log.info("随机生成的token=============: {}",token);
        //7.2将User对象转为Hash存储
        UserDTO userDTO =  BeanUtil.copyProperties(user,UserDTO.class);
        Map<String,Object> userMap = BeanUtil.beanToMap(userDTO,new HashMap<>(),
                CopyOptions.create()
                        .setIgnoreNullValue(true)
                        .setFieldValueEditor((fieldName, fieldValue) -> String.valueOf(fieldValue )));
        //7.3存储
        String key = LOGIN_USER_KEY + token;
        stringRedisTemplate.opsForHash().putAll(key,userMap);
        //7.4设置token有效期
        stringRedisTemplate.expire(key,LOGIN_USER_TTL,TimeUnit.MINUTES);
        return Result.ok(token);
    }

    /**
     * 根据id查询用户信息
     * @param userId 用户id
     * @return UserDTO对象
     */
    @Override
    public UserDTO queryUserById(Long userId) {
        User user = getById(userId);
        if (user == null){
            return new UserDTO();
        }
        return BeanUtil.copyProperties(user, UserDTO.class);
    }

    /**
     * 实现用户签到
     * @return 无
     */
    @Override
    public Result sign() {
        //1.获取当前用户
        Long userId = UserHolder.getUser().getId();
        //2.获取日期
        LocalDateTime now = LocalDateTime.now();
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = USER_SIGN_KEY + userId + keySuffix;

        //3.获取今天是本月的第几天
        int dayOfMonth = now.getDayOfMonth();
        //4.写入redis setBit key offset 1  (offset是从0开始)
        stringRedisTemplate.opsForValue().setBit(key,dayOfMonth - 1,true);
        return Result.ok();
    }

    /**
     * 进行一个月中的签到统计
     * @return 无
     */
    @Override
    public Result signCount() {
        //1.获取当前用户
        Long userId = UserHolder.getUser().getId();
        //2.获取日期
        LocalDateTime now = LocalDateTime.now();
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = USER_SIGN_KEY + userId + keySuffix;

        //3.获取今天是本月的第几天
        int dayOfMonth = now.getDayOfMonth();

        //4.获取本月截止到今天所有的签到记录，返回的是一个十进制的数字
        // bitfield sign:5:202203 get u(dayOfMonth-1) 0
        List<Long> result = stringRedisTemplate.opsForValue().bitField(key,
                BitFieldSubCommands.create()
                        .get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0)
        );
        if (result == null || result.isEmpty()){
            return Result.ok(0);
        }

        Long num = result.get(0);
        if (num == null || num == 0){
            return Result.ok(0);
        }

        //遍历循环
        int count = 0;
        while (true){
            //6.1.让这个数字与1做与运算，得到数字的最后一个bit为 判断这个bit位是否为0
            if ((num & 1) == 0){
                break;
            }else {
                count++;
            }
            //数字右移一位，抛弃最后一个bit
            num >>>= 1;
        }
        return Result.ok(count);
    }

    @Override
    public void logout() {

        return;

    }



    /*@Override
    public Result logout() {
        Boolean result = stringRedisTemplate.delete(String.valueOf(logoutToken));
        if (result){
            log.info("登出成功==============:token{}",logoutToken);
            return Result.ok();
        }
        log.info("登出失败================token:{}",logoutToken);
        return Result.fail("登出失败");
    }*/

    /**
     * 创建全新用户
     * @param phone 手机号
     * @return user用户
     */
    public User createUserWithPhone(String phone) {
        User user = new User();
        user.setPhone(phone);
        log.info("创建全新用户函数里的phone：{}",phone);
        user.setNickName(USER_NICK_NAME_PREFIX + RandomUtil.randomString(10));
        //保存
        try {
            save(user);
            log.info("保存到数据库完成了");
        } catch (Exception e) {
            log.info("保存到数据库失败");
        }
        return user;
    }


}
